No signal my vizio will turn on,"no signal" appears then turns off by itself after 2 seconds.

Vizio TVs have an auto-off function intended as a power-saving feature. By default, the TV will turn itself off if it detects no signal for ten minutes. You can disable the Auto Power Off feature from the sleep timer menu.

If I have trouble with a brand new TV I always take it back and am sure to get another brand entirely. Personally I've had good luck with LG, SEIKI, and Samsung.

you'll need to do a master reset of the device

check link -->

www.retrevo.com/support/Vizio-L32-TVs-manual/id/512dj084/t/2

Usually when VGA or PC input selected TV come on, says NO SIGNAL, and turn itself off. After turnin on you have few seconds to change tv input.

If your television is displaying a blue screen or no signal message and then turning off, your TV may be at an inactive input. Here's how you can get back to watching your TV:
1. Powering on your TV and press the INPUT button on the VIZIO remote control repeatedly until a picture re-appears.
2. If this does not work, try again but press the button slower this time.

I got this off the vizio website.

Unplug the TV from Wall, wait a bit and plug back in. Should be reset.

HERE'S THE FIX: I just went through this with my Vizio VX37L. TV is stuck in RGB input. This is the fix.... TV is stuck in RGB input.
(option 1) Power on TV, and press the INPUT button repeatedly and rapidly until you can change to a different input, such as AV.
If that doesn't work, try:
(option 2) With the TV off, press and hold the INPUT button on the side of the TV for about 5 seconds. The TV should power on and the input list will appear. The TV will no longer be locked, and the INPUT button should function properly after that.

Option 2 worked for me!

Turn the television on and as soon as the screen turns on repeatily press the input button or change the input to whatever input you are using from a source device. As long as you change it to anything other than RGB.

Your television is essentially a big computer monitor with multiple inputs and a tuner. When using your computer and shutting it down the monitor will go in a power save mode. You don't need to shut off your monitor due to this power saving mode. When you power up your computer your monitor automatically turn on.

With the VIZIO and the RGB (computer) input the television will act just like a computer monitor. When you have a computer connected it will power down automatically when you shut off your computer. When you turn your computer on the VIZIO will automatically come out of standby mode. This is through RGB only.

This is normal operation for the VIZIO but can see confusing when nothing is connected to the RGB input. If you change your television input to RGB it will sense no signal on the input and will go into standby mode after about 5 - 10 seconds. If you were to send a signal to the television through RGB it would automatically kick on.

if the TV have a no signal sign which means most of the important part is missing. Try checking your connections. The best way is to hook up a dvd player using AV input (the yellow, red and white). make sure that you turn the device on and whatever input you connected the device to is selected. if your TV is a P50HDM model, the TV will shut itself off after a short period without and input connected.

Just hold down the input button on the right side of the tv. This is the bottom one. So,
With the tv off,
press and hold the bottom button (input)
when the tv turns on, and you see the input menu
release and press the button to put the tv into a mode that works!
Thanks